Whisk together the eggs, sugar, and salt in a mixing bowl until everything is nicely blended.
In a separate bowl, stir the instant yeast into warm milk. Be sure the milk is warm, not hot, so the yeast stays active. Pour this mixture into the egg bowl, add the melted butter, and whisk again to bring it all together.
Add the flour to the wet ingredients and begin kneading. You can use a stand mixer fitted with a dough hook, or work the dough by hand until it becomes smooth and elastic.
Lightly oil a clean bowl, place the dough inside, cover it, and leave it to rise slowly in the fridge for a minimum of 3 hours. If you prefer, you can refrigerate it overnight (up to 12–16 hours).
When it’s time to shape the donuts, dust your work surface well or use baking paper. Give the chilled dough a quick, gentle knead, then roll it out to about 1.5 cm thick. Avoid going thinner or thicker, as it affects how the donuts fry.
Use a round cutter to stamp out as many donuts as you can. Gather the scraps, roll them out again, and continue cutting until all the dough is used. Set each donut onto its own square of baking paper; this makes transferring them into the oil so much easier.
Cover the shaped donuts and let them rise for 30-45 minutes. While they proof, heat your oil to around 170°C. Using a thermometer is ideal, as it helps prevent greasy donuts from oil that’s too cool or pale outsides with raw centers from oil that’s too hot.
Fry the donuts for roughly 90 seconds per side, until they turn a deep golden colour. Lift them out onto paper towels to drain off excess oil. Allow them to cool completely before adding your filling.
Apple Pie Filling: In a saucepan, add the apples, brown sugar, and cinnamon powder. Mix well, then cover and cook on medium heat for 10-15 minutes until the apples are soft and coated well with the caramel sauce. Let it cool completely and place it in a piping bag, ready to use.
Cinnamon Butter: In a bowl, whisk together the butter, brown sugar, and cinnamon until fully combined and smooth. Place in piping bag ready to use.
Cream Cheese Glaze: In a bowl, add the cream cheese, butter, icing sugar, and vanilla essence and whisk on high speed until fully combined and smooth. If the glaze is too thick, add a little milk to thin it out.
Coffee Cream: Place the coffee powder, sugar, and water in a bowl and whisk on high for 3-5 minutes until pale and frothy. Add the cream and whisk on high until it reaces medium peaks. Place in a piping bag ready to use.
Mascarpone Glaze: In a bowl, add the mascarpone, butter, icing sugar, and vanilla essence and whisk on high speed until fully combined and smooth. If the glaze is too thick, add a little milk to thin it out.
Sticky Date Filling: Place the dates and water in a saucepan, cover, and cook until softened, then blend until fully smooth. Let it cool completely and place it in a piping bag, ready to use.
Butterscotch Glaze: Place the brown sugar, butter, and cream in a saucepan, mix until the butter is melted and combined with the sugar, then let it cook for 2-3 minutes on medium heat until thickened. Let it cool completely before using.
Chocolate Ganache: Place the chopped chocolate in a heat-proof bowl. Heat the cream in a saucepan until it starts to simmer, then pour it over the chocolate, let it melt, and whisk until fully melted and combined. Let it cool completely before using. Place half the ganache in a piping bag and the remaining in a bowl for glazing.
Salted Caramel Sauce: Place the sugar in a saucepan on medium heat, let it melt, mixing often with a spatula, until fully melted and amber in color. Add the butter, whisk until combined, and cook for a minute, then carefully whisk in the cream and cook for 2 minutes. Take off the heat and mix in the salt. Let it cool completely and place it in a piping bag, ready to use.
Whipped Cream: Place the cream and icing sugar in a bowl and whisk on high speed until it reaches medium peaks. Place in a piping bag with any frosting tip of your choice.
Apple Pie Donuts: Fill the donuts with the apple pie filling, then dip them into the cream cheese glaze. Pipe a swirl of whipped cream on top with a dollop of apple pie in the center.
Cinnamon Roll Donuts: Fill the donuts with the cinnamon butter filling, then dip them into the cream cheese glaze. Add a dusting of cinnamon powder on top.
Tiramisu Donuts: Fill the donuts with the coffee cream filling, then dip them into the mascarpone cheese glaze. Add a dusting of cocoa powder on top and a small piece of ladyfinger biscuit (optional).
Sticky Toffee Pudding Donuts: Fill the donuts with the date filling, then dip them into the butterscotch glaze. Pipe a swirl of whipped cream on top.
Hot Chocolate Donuts: Fill the donuts with the thick ganache filling, then dip them into the same ganache, but microwave it before to thin it out into a glaze-like consistency. Pipe a swirl of whipped cream on top with a mini marshmallow in the center.
Salted Caramel Chocolate Donuts: Fill the donuts with the salted caramel filling, then dip them into the thinned-out chocolate ganache glaze. Top with chocolate shavings.